import java.util.Scanner;
public class videoSpeedUpCaler 
{
  static float after_speed_up_time(int hour,int minute,int beisu)
  {
    return (hour * 60 + minute)/beisu;
  }
  public static void main(String[] args) 
  {
    Scanner sc = new Scanner(System.in);
    int hour,minute,beisu;
    System.out.println("enter video time hour");
    hour = sc.nextInt();
    System.out.println("enter video time minute");
    minute = sc.nextInt();
    System.out.println("enter video speed");
    beisu = sc.nextInt();
    float time = after_speed_up_time(hour,minute,beisu);
    System.out.println("after speed up" + time + "minute");
  }
}